/*
 * Copyright (C) 2007 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.example.android.apis.graphics;

// Need the following import to get access to the app resources, since this
// class is in a sub-package.
//import com.example.android.apis.R;

import android.content.Context;
import android.graphics.*;
import android.os.Bundle;
import android.view.View;

public class PolyToPoly extends GraphicsActivity {

	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(new SampleView(this));
	}

	private static class SampleView extends View {
		private Paint mPaint = new Paint(Paint.ANTI_ALIAS_FLAG);
		private Matrix mMatrix = new Matrix();
		private Paint.FontMetrics mFontMetrics;

		private void doDraw(Canvas canvas, float src[], float dst[]) {
			canvas.save();
			mMatrix.setPolyToPoly(src, 0, dst, 0, src.length >> 1);
			canvas.concat(mMatrix);

			mPaint.setColor(Color.GRAY);
			mPaint.setStyle(Paint.Style.STROKE);
			canvas.drawRect(0, 0, 64, 64, mPaint);
			canvas.drawLine(0, 0, 64, 64, mPaint);
			canvas.drawLine(0, 64, 64, 0, mPaint);

			mPaint.setColor(Color.RED);
			mPaint.setStyle(Paint.Style.FILL);
			// how to draw the text center on our square
			// centering in X is easy... use alignment (and X at midpoint)
			float x = 64 / 2;
			// centering in Y, we need to measure ascent/descent first
			float y = 64 / 2 - (mFontMetrics.ascent + mFontMetrics.descent) / 2;
			canvas.drawText(src.length / 2 + "", x, y, mPaint);

			canvas.restore();
		}

		public SampleView(Context context) {
			super(context);

			// for when the style is STROKE
			mPaint.setStrokeWidth(4);
			// for when we draw text
			mPaint.setTextSize(40);
			mPaint.setTextAlign(Paint.Align.CENTER);
			mFontMetrics = mPaint.getFontMetrics();
		}

		@Override
		protected void onDraw(Canvas canvas) {
			canvas.drawColor(Color.WHITE);

			canvas.save();
			canvas.translate(10, 10);
			// translate (1 point)
			doDraw(canvas, new float[] { 0, 0 }, new float[] { 5, 5 });
			canvas.restore();

			canvas.save();
			canvas.translate(160, 10);
			// rotate/uniform-scale (2 points)
			doDraw(canvas, new float[] { 32, 32, 64, 32 }, new float[] { 32,
					32, 64, 48 });
			canvas.restore();

			canvas.save();
			canvas.translate(10, 110);
			// rotate/skew (3 points)
			doDraw(canvas, new float[] { 0, 0, 64, 0, 0, 64 }, new float[] { 0,
					0, 96, 0, 24, 64 });
			canvas.restore();

			canvas.save();
			canvas.translate(160, 110);
			// perspective (4 points)
			doDraw(canvas, new float[] { 0, 0, 64, 0, 64, 64, 0, 64 },
					new float[] { 0, 0, 96, 0, 64, 96, 0, 64 });
			canvas.restore();
		}
	}
}
